Suborder RECTANGULINA Waters, 1887

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Introduction

The name Rectangulina is used here to replace the name Rectangulata. This distinctive suborder comprises the single family Lichenoporidae. It was first defined by Waters (1887) and its morphology was detailed by Borg (1926, 1944), who introduced the alternative name Calyptostega. The ancestrula develops a cone of gymnocystal skeleton bounding the growth zone which broadens, opens and recurves to cover its origin, forming a basal lamina with a peripheral growing edge. Calcification of zooids is entirely cryptocystal. Zooids bud and grow radially, in connate rows or quincuncial series; these diverge towards the colony rim leaving spaces between, termed alveoli, which may be subdivided by extrazooidal cryptocystal calcification, and in some genera entirely closed. The brood chamber commences as a modified zooid, the body wall of which breaks down, becoming confluent with extrazooidal space and forming a colonial brood chamber. This develops a texturally distinct roof, with a tubular or flared ooeciostome.

General References

Borg, F. 1926. Studies on Recent cyclostomatous Bryozoa. Zoologiska Bidrag Från Uppsala 10: 181-507

Borg, F. 1944. The stenolaematous Bryozoa. Further Zoological Results of the Swedish Antarctic Expedition, 1901-1903 3(5): 1-276

Waters, A.W. 1887. On Tertiary cyclostomatous Bryozoa from New Zealand. Quarterly Journal of the Geological Society of London 43: 337-350

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